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Position
Lies above and behind the medullar and pons and occupies posterior cranial fossa
Cerebellum
Cerebellum Cerebellum External External ConfigurationsConfigurations
Cerebellum Cerebellum External External ConfigurationsConfigurations
• Located in Located in posterior cranial fossaposterior cranial fossa• Tentorium cerebelli (cerebrum), 4Tentorium cerebelli (cerebrum), 4thth ventricle (brain stem)ventricle (brain stem)• Communicate with other structure viaCommunicate with other structure via
•superior, middle, and inferior superior, middle, and inferior cerebellar pedunclecerebellar peduncle
External features
Three peduncles Inferior cerebellar peduncle
下小腦脚 - connect with medulla and with spinal cord, contain both afferent and efferent fibers
Middle cerebellar peduncle 中小腦脚- connect with pons, contain afferent fibers
Superior cerebellar peduncle 上小腦脚- connect with midbrain, contain mostly efferent fibers
Cerebellum
Longitudinal division Vermis, Paravermal Region, Cerebellar
Hemisphere Transverse division
Anterior Lobe Posterior Lobe Flocculonodular Lobe
Lobes
Primary fissure
Posterolateral fissureFlocculonodular lobe
Anterior lobe
Posterior lobe
corpus of cerebellar
Lobes Two deep fissures
Primary fissure
Posterosuperior fissure
Three lobs
Flocculonodular lobe 絨球小結葉 flocculus and nodule
Anterior lobe
Posterior lobe
Corpus of cerebellar
External features
Tonsil of cerebellum 小腦扁桃体 two elevated masses on inferior surface of hemispheral portion just nearby foramen magnum
Tonsil
Superior surface
View from below
Subdivision ofSubdivision of Flocculonodular Lobe Flocculonodular Lobe
Nodulus FlocculusNodulus Flocculus
Subdivision of Subdivision of Anterior LobeAnterior Lobe
Vermis HemisphereVermis Hemisphere
LingulaLingulaCentral Lobule Central Lobule Ala Central LobuleAla Central Lobule
postcentral fissurepostcentral fissure
Culmen Culmen Quadriangular LobuleQuadriangular Lobule
Cerebellum Cerebellum External External ConfigurationsConfigurations
Cerebellum Cerebellum External External ConfigurationsConfigurations
Subdivision of Subdivision of Posterior LobePosterior Lobe
Vermis HemisphereVermis Hemisphere
Declive Declive Simple LobuleSimple Lobule
postcentral fissurepostcentral fissure
FoliumFolium Superior Semilunar LobuleSuperior Semilunar Lobule horizontal fissurehorizontal fissure
Inferior Semilunar LobuleInferior Semilunar Lobule Tuber Tuber Gracile LobuleGracile Lobule prepyramidal fissureprepyramidal fissure
Pyramis Pyramis Biventer LobuleBiventer Lobule
secondary fissuresecondary fissure
Uvula Uvula TonsilTonsil
Cerebellum Cerebellum External External ConfigurationsConfigurations
Cerebellum Cerebellum External External ConfigurationsConfigurations
Cerebellar Cortex
Molecular Layer Purkinje Cell Layer Granular Layer
Corpus Medullare (Medullary Center)
Deep Cerebellar Nuclei
Fastigial Nuclei Nucleus Interpositus Emboliform Nucleus Globose Nucleus Dentate Nucleus
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
Internal structures Gray matter Cerebellar cortex Cerebellar nuclei
Dentate nucleus 齒狀核 Fastigial nucleus 頂核 Interposed nucleus 中間核
Emboliform nucleus 栓狀核 Globose nucleus球狀核
White matter -medullary center 髓体
1. fastigial 1. fastigial
nucleusnucleus
2. globose 2. globose
nucleusnucleus
3. emboliform 3. emboliform
nucleusnucleus
4. dentate 4. dentate
nucleusnucleus
Deep NucleiDeep Nuclei
Internal structures
Cerebellar cortex
Dentate nucleus
Fastigial nucleus
Globose nucleus
Emboliform nucleus
medullary center
Cerebellar CortexInputs
Output
Interneurons
Climbing fibers•from Inferior olive
Mossy fibers
Purkinje neurons
Stellate neurons
Granule neurons
Basket neurons
Golgi neuronsMolecular
PurkinjeGranular
NTA Fig. 13-11
Cerebellar Cortex
I. Molecular Layer
Stellate Cell --- taurine (inhibitory) afferent: parallel fiber efferent: Purkinje cell dendrite Basket Cell ---- GABA (inhibitory) afferent: parallel fiber efferent: Purkinje cell soma Parallel Fiber granule cell axon Purkinje Cell Dendrite
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
Cerebellar Cortex
II. Purkinje Cell Layer
Purkinje Cell -- 15,000,000 in number -- GABA (inhibitory) afferent from: parallel fiber climbing fiber stellate cell basket cell efferent to: deep cortical nuclei
Bergman’s glial cell
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
Cerebellar Cortex
III. Granular LayerIII. Granular Layer
Granular Cell Granular Cell -- 50,000,000,000 in number-- 50,000,000,000 in number -- glutamic acid (excitatory)-- glutamic acid (excitatory) afferent: afferent: mossy fibermossy fiber efferent: efferent: Purkinje cell dendritePurkinje cell dendrite basket cell, stellate cellbasket cell, stellate cell Golgi cellGolgi cell
Golgi CellGolgi Cell -- GABA (inhibitory)-- GABA (inhibitory) afferent: parallel fiber, mossy fiber rosetteafferent: parallel fiber, mossy fiber rosette efferent: granule cell dendriteefferent: granule cell dendrite
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
1. Purkinje cell
2. granule cell
3. basket cell
4. Golgi cell
5. stellate cell
6. climbing fiber
7. mossy fiber
8. parallel fiber
9. inferior olivary nucleus
10. deep cerebellar nuclei
Synaptic Glomerulus
Afferent terminals on granular layerAfferent terminals on granular layer
Mossy Fiber Rosette Mossy Fiber Rosette -- afferent fibers except-- afferent fibers except inferior olivary inputinferior olivary input -- 2/3 of medullary center-- 2/3 of medullary center
Granular Cell Dendrite Granular Cell Dendrite -- main afferent input -- main afferent input
Golgi Cell Axon Golgi Cell Axon -- synapse on granule cell dendrite-- synapse on granule cell dendrite -- GABA (inhibitory)-- GABA (inhibitory)
- - Surrounded by Surrounded by AstrocyteAstrocyte Foot Process Foot Process
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
Cerebellum Cerebellum Internal Internal ConfigurationsConfigurations
Classification by Phylogenetic and Ontogenic Development
ArchicerebellumArchicerebellum PaleocerebllumPaleocerebllum NeocerebellumNeocerebellum
Classification by Afferent Connection
VestibulocerebellumVestibulocerebellum SpinocerebellumSpinocerebellum PontocerebellumPontocerebellum
Classification by Efferent Connection
VermisVermis Paravermal RegionParavermal Region Cerebellar HemisphereCerebellar Hemisphere
Cerebellum Cerebellum ClassificationsClassifications
Cerebellum Cerebellum ClassificationsClassifications
Afferent Connections (1):
1. Inferior Cerebellar Peduncle1. Inferior Cerebellar Peduncle
Restiform BodyRestiform Body Posterior Spinocerebellar TractPosterior Spinocerebellar Tract Olivocerebellar tractOlivocerebellar tract Cuneocerebellar TractCuneocerebellar Tract Reticulocerebellar TractReticulocerebellar Tract
Juxtarestiform BodyJuxtarestiform Body Vestibulocerebellar TractVestibulocerebellar Tract Primary Vestyibular FiberPrimary Vestyibular Fiber
Cerebellum Cerebellum ConnectionsConnections
Cerebellum Cerebellum ConnectionsConnections
Afferent Connections (2):
2. Middle Cerebellar Peduncle2. Middle Cerebellar Peduncle
Pontocerebellar fiberPontocerebellar fiber Corticopontocerebellar FiberCorticopontocerebellar Fiber Reticulocerebellar FiberReticulocerebellar Fiber
3. Superior Cerebellar Peduncle3. Superior Cerebellar Peduncle
Anterior Spinocerebellar TractAnterior Spinocerebellar Tract Cerulocerebellar fiberCerulocerebellar fiber Raphecerebellar fiberRaphecerebellar fiber Rubrocerebellar fiberRubrocerebellar fiber Hypothalamocerebellar fiberHypothalamocerebellar fiber
Cerebellum Cerebellum ConnectionsConnections
Cerebellum Cerebellum ConnectionsConnections
Efferent Connections :
1. Superior Cerebellar Peduncle
Cerebellothalamic fiber - from 3 deep nuclei to VPLo, VLc, CL Cerebellorubral fiber - from nucleus interpositus and dentate nucleus ascending portion of uncinate fasciculus of Russell 2. Inferior Cerebellar Peduncle
Fastigiovestibular fiber descending portion of uncinate fasciculus of Russell
Cerebellum Cerebellum ConnectionsConnections
Cerebellum Cerebellum ConnectionsConnections
Three functional divisions Vestibulocerebellum
前庭小腦 Archicerebellum 原小
腦 Flocculonodular lobe
Spinocerebellum 脊髓小腦 Paleocerebellum 舊小
腦 Vermis and intermediate zone
Cerebrocerebellum 大腦小腦 Neocerebellum 新小腦 Lateral zone
Flocculonodular lobe
Verm
is In
termed
iate zo
ne
Lateral
zon
e
IVth vent VermisIntermediate hem.
Spinocerebellum: Vermis Intermediate hem.Spinocerebellum
(Vermis + Intermed. Hem)
Control of limbs and trunk
Lateral hem.
Cerebrocerebellum: Lateral hem.
Cerebrocerebellum(Lateral hemisphere)
Planning of movement+
Floculo-nodular lobe
Vestibulo-cerebellum(Floculo-nodular lobe)
Control of eye & head movementsBalance
Cerebellar divisions
NTA Fig. 13-1
Connections and function of cerebellum Vestibulocerebellum
Connections Afferents: receive input from vestibular nuclei and
primary vestibular Efferents: projects to the vestibular nucleus →
(1) vestibulospinal tract → motor neurons of anterior horn for reflexively control of equilibrium
(2) vestibulo-ocular tract → medial longitudinal fasciculus → CN nucleus 3, 4, 6 for EOM control.
Function: involved in eye movements and maintain balance
MLFMLF
Main Connections of the VestibulocerebellumMain Connections of the VestibulocerebellumMain Connections of the VestibulocerebellumMain Connections of the Vestibulocerebellum
lower motor neuronlower motor neuron
LMNLMN
vestibulospinal tractvestibulospinal tract
FASTIGIALFASTIGIAL NUCLEUSNUCLEUS
VestibularVestibular OrganOrgan FloculonodularFloculonodular
LobeLobe VermisVermis
ARCHICEREBELLUMARCHICEREBELLUM
VESTIBULAR NUCLEUSVESTIBULAR NUCLEUS
Main Connections of the PaleocerebellumMain Connections of the PaleocerebellumMain Connections of the PaleocerebellumMain Connections of the Paleocerebellum
lower motor neuronlower motor neuron
SPINAL CORDSPINAL CORD
rubrospinal rubrospinal tracttract
NUCLEUSNUCLEUSINTERPOSITUSINTERPOSITUS
InferiorInferior OlivryOlivryNucleusNucleus
ANTERIOR ANTERIOR LOBELOBEPARAVERMAL PARAVERMAL ZONEZONE
PALEOCEREBELLUMPALEOCEREBELLUM
RED RED NUCLEUSNUCLEUS
spinocerebellar tractspinocerebellar tract
Spinocerebellar tracts
End mainly in the anterior lobe, the paramedian lobule, and the pyramis of the posterior lobe
Connections and function of cerebellum
Cerebrocerebellum Connection
Afferents: receives input from the cerebral cortex via a relay in pontine nuclei
Efferents: projects to dentate nucleus → VI → primary motor cortex → corticospinal tract → motor neurons of anterior horn
Function: participates in planning movements
CEREBRALCEREBRAL CORTEXCORTEX
CEREBRALCEREBRAL CORTEXCORTEX DENTATEDENTATE
NUCLEUSNUCLEUS
DENTATEDENTATENUCLEUSNUCLEUS
Main Connections of the NeocerebellumMain Connections of the Neocerebellum
lower motor neuronlower motor neuron
LMNLMN
pyramidal pyramidal tracttract POSTERIOR POSTERIOR
LOBELOBECEREBELLARCEREBELLAR HEMISPHEREHEMISPHERE
POSTERIOR POSTERIOR LOBELOBE
CEREBELLARCEREBELLAR HEMISPHEREHEMISPHERE
THALAMUSTHALAMUSTHALAMUSTHALAMUS
NEOCEREBELLUMNEOCEREBELLUM
PontinePontineNucleusNucleusPontinePontineNucleusNucleus
upper motor neuronupper motor neuron
UMNUMN
upper motor neuronupper motor neuron
UMNUMN
BASALBASALGANGLIAGANGLIA
BASALBASALGANGLIAGANGLIA
Pyramidal Tract and Associated CircuitsPyramidal Tract and Associated CircuitsPyramidal Tract and Associated CircuitsPyramidal Tract and Associated Circuits
lower motor neuronlower motor neuron
UMNUMN
lower motor neuronlower motor neuron
UMNUMN
pyramidal tractpyramidal tract
CerebellumCerebellumCerebellumCerebellum
ReticularFormation
ReticularFormation
CEREBELLUMCEREBELLUM
Cerebellum and Automatic Motor ControlCerebellum and Automatic Motor ControlCerebellum and Automatic Motor ControlCerebellum and Automatic Motor Control
Lower Motor Neuron (LMN)Lower Motor Neuron (LMN)Lower Motor Neuron (LMN)Lower Motor Neuron (LMN)
Motor CortexMotor Cortex
Red NucleusRed Nucleus
Vestibular Nucleus
Vestibular Nucleus
ProprioceptorsProprioceptorsProprioceptorsProprioceptors
Cerebellum---- connection
Corticonuclear Connections
A zone ---------- fastigial nucleus medial vestibular nucleus B zone ---------- lateral vestibular nucleus C1, C3 zone --- emboliform nucleus C2 ---------------- globose nucleus D1 ---------------- parvocellular portion of dentate nucleus D2 ---------------- magnocellular portion of dentate nucleus
1. vermis
2. paravermal region
3. cerebella hemisphere
4. nodulus
5. flocculus
6. fastigial nucleus
7. globose nucleus
8. emboliform nucleus
9. dentate nucleus
10. medial vestibular nucleus
11. lateral vestibular nucleus
Olivocerebellar Connections
(1) Caudal portion of medial and dorsal accessory olivary nucleus ----------------- vermis of cerebellar cortex (A and B) fastigial nucleus vestibular nucleus
(2) Rostral portion of medial and dorsal accessory olivary nucleus ----------------- paravermal region (C1, C2, C3) nucleus interpositus
(3) Principal Inferior Olivary Nucleus ----------------- cerebellar hemisphere (D1, D2) dentate nucleus
Cerebellum Cerebellum ConnectionsConnections
Cerebellum Cerebellum ConnectionsConnections
Olivo-cerebellar system The inferior olivary complex
Principal olive, medial and dorsal accessory olive, and medial lamina. 1.5 million cells
Send climbing fibers to all cerebellar cortex in a specific topographic manner A Small area in the inferior olive is linked to a definite area of
the cerebellar output
The inferior olivary complex Receives projections from
The spinal cord crossed ventral and dorsal spino-olivary tracts
The brainstem (esp. red nuclei) Cerebellar nuclei
Interpositus & dentate nuclei exert an inhibitory effect Pretectal nuclei
Relaying optokinetic information Cerebrum
Motor cortex (area 4), premotor cortex (area 6) Visual and Vestibular areas Zona incerta of the thalamus
Relay for the projections from the motor cortex, prefrontal, cingulate, parietal and temporal area
medial and dorsal accessory olivary nucleusmedial and dorsal accessory olivary nucleus
caudal portioncaudal portion rostral portion rostral portion Principal Principal Inferior Olivary Inferior Olivary
NucleusNucleus
Functional divisions of cerebellar cortex
VermisIntermediate hem
CerebrocerebellumLateral hemisphere
Spinocerebellum
Vestibulo-cerebellumFloculo-nodularlobe
Functional divisions of cerebellar cortex --> Deep nuclei
CerebrocerebellumLateral hemisphere
Dentate
Fastigial
To medialsysetms
To frontalmotor areas
MotorPlanning +++
Motorexecution
Vestibulo-cerebellum
To vestibular nuclei
Eye mvt &balance
Reticular nuclei
Lateral reticular nuclei (lateral to inferior olive) Sent mossy fibers to bilateral cerebellum (ipsilateral
dominant) via superior cerebellar peduncle. Receive excitatory reciprocal input from the cerebellar
nuclei Receive collaterals from propiospinal neurons
Relay motor information to cerebellum
CerebellumCerebellum FunctionFunction
CerebellumCerebellum FunctionFunction
Maintenance of Equilibrium - balance, posture, eye movement
Coordination of half-automatic movement of walking and posture maintenance - posture, gait
Adjustment of Muscle Tone
Motor Leaning – Motor Skills
Cognitive Function
CerebellumCerebellum Clinical Clinical SyndromesSyndromes
CerebellumCerebellum Clinical Clinical SyndromesSyndromes
Ataxia: incoordination of movement - decomposition of movement - dysmetria, past-pointing - dysdiadochokinesia - rebound phenomenon of Holmes - gait ataxia, truncal ataxia, titubationIntention TremorHypotonia, Nystagmus
Archicerebellar LesionArchicerebellar Lesion: medulloblastoma: medulloblastomaPaleocerebellar LesionPaleocerebellar Lesion: gait disturbance: gait disturbanceNeocerebellar LesionNeocerebellar Lesion: hypotonia, ataxia, tremor: hypotonia, ataxia, tremor
Cerebellar Cerebellar AtaxiaAtaxia
Ataxic gait and Ataxic gait and position: position: Left cerebellar tumorLeft cerebellar tumor
a. Sways to the right ina. Sways to the right in standing positionstanding position
b. Steady on the b. Steady on the right legright leg
c. Unsteady on the c. Unsteady on the left legleft leg
d. ataxic gaitd. ataxic gait
a b c
d
Cerebellar tumors on vermisCerebellar tumors on vermis
- Truncal Ataxia- Truncal Ataxia
- Frequent Falling- Frequent Falling
The child in this picture:The child in this picture:
- would not try to stand - would not try to stand unsupportedunsupported
- would not let go of the bed rail- would not let go of the bed rail if she was stood on the floor.if she was stood on the floor.
Cerebellar Medulloblastoma